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LCD Monitor For Your Eyes Only
Bryan_Casto writes "USAToday has an article about Sceptre's new LCD monitor, which hides the screen image from anyone not wearing the glasses that come with the monitor. The screen appears white to ordinary eyes, but with the polarized glasses, the desktop comes into view. "
I think that may have been the worst movie I've ever seen. We were watching it one night at Vermont Tech, 'cause there wasn't anything else to do, and we only got one channel... they kept going to commercial break, showing *one* commercial, then going back to the movie...
We were sitting around yelling, "More commercials! No! Not the movie! Ahhh! We want to see more commercials!" at the TV screen.
What company is going to buy this for their employees? I think 1) most bosses want to know if their employees are working and not going to girlie sites and 2) if people are surfing the web when they're not supposed to they'll be logged on the server anyway.
No one will buy this at home. If you're single, you don't need to hide anything. If you're married your spouse will want to know if your doing something you shouldn't. (Will cause many headaches and arguments.)
The only possible customer would be those working on confidential/secret/top secret documents and I doubt the Govt. is going to spend extra money for this.
I think this monitor will have a very small clientelle. Maybe conspiracy theorists...
Misfit
"Excellence for all the world to see"
Ironic, eh?
This will be great for our sysadmin/netadmin. Instead of having to painfully minimize his porn sessions when someone walks by, he can just wear his glasses all day. Neat!
Most polarization displays use rotational polarization, not linear. That is, the curl of the photons matters, rather than the... the whatever it is that is affected by linear polarization. :) Rotation doesn't matter in such situations, nor does which way the polarizer is plunked down (corkscrews remain with the same winding no matter how they're put down); the only real drawback (again, for this situation) is that you have to have two distinct polarizers rather than being able to have two of the same and just turn one 1.57079632679489661923132169 radians.
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"'Is not a quine' is not a quine" is a quine.
"'Is not a quine' is not a quine" is a quine.
Quine "quine?
According to previous posters, this works by taking the top polarizing filter off the LCD panel and putting in some "sunglasses" instead.
So, don't look directly at the panel. Look instead at its reflection in the surface of the desk. Most surfaces reflect polarized light. This is why Polaroid sunglasses work at all; they reduce glare by mounting polarizers at 90 degrees to the polarized axis of the reflected light.
Since the light coming off the panel is already polarized, when it bounces off the surface of the desk (which is a natural polarizer), the display's reflection should be somewhat intelligible. They have an exhibit demonstrating this sort of thing in San Francisco's Exploratorium.
Schwab
Editor, A1-AAA AmeriCaptions
Most sunglasses are "polarized" these days. You could probably use them to spy on the person's screen without drawing any attention to yourself.
Another form of security through obscurity?
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sounds rather worthless to me... anyone w/ polarized glasses can see everyone else's screens. this is barely a step above talking in pig latin for "secrecy".
This is just a normal LCD display with the front polarizer removed. Anyone else with a polarizer could see it too.
The problem with wearing these in public, like on the subway, is that you also get to (unfortunately) see all the other signs that already use this technology subliminally. All those "Obey" and "Sleep" and "Marry and Reproduce" signs would get depressing after a while.
As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
I did this with my old ThinkPad 350C it looks pretty sweet. I fully recommend that anyone with an old portable that they want to play around with gives it a shot. The trick is getting the screen cover to pop off, some models are harder than others. But if you can get the top polarized filter out you're golden. Then just replace the top filter with a piece of clear sturdy plastic about the smae thickness (plexiglass works great of you can find it that thin.) Get a pair of old school snowboarding goggles and cut out circles from the filter you removed and fasten them to the inside of the goggles and WALA! Stealth computing. It looks pretty fly when you're hacking away at your portable and there's nothing but a blank screen in front of you.
And if you really wanna be smooth, try painting over the characters on the keyboard so you have a completely blank terminal in front of you. My thinkpad looks cool this way.
The way these things work, obviously, is by polarization - IIRC, the LCD elements are sandwiched between two polarizing sheets - the first sheet gives the light (from the backlight) a twist 90 degrees, and the second gives another 90 degree twist. What an LCD element does is give a third (actually, a second) 90 degree twist to allow the light to be seen...
Now, if the polarizer on the front and back of the LCD could be positioned at a different angle (and at very minute steps), the 90 degree twisty thingy would still work (since the LCD is probably standard), but you would need the glasses to be at the same angle in order to view the image. These glasses, of course, would be matching glasses to the LCD (order many pairs!), and if the manufacturer varied the angle at small angles (and even possibly a different random angle on each LCD made in sequence), then each monitor would be unique (sorta like Master Lock Combo Locks are unique). However, I doubt any manufacturer would do this...
There are, of course, problems with such a system - mainly, you need to hold you head level - any deviation and the screen goes blank (of course, this affects the current set up). You would also have co-workers running around the office with polarizing sunglasses on waggling thier heads crazily (Ow! My neck! Workman's comp!) - I don't know which would be funnier; guessing who is looking at pr0n or watching the head wagglers!
Anyhow - no matter what - this is security by obscurity at best. But how about this...
What if the glasses were active - say high speed shutter glasses timed to the refresh rate of the monitor. Now, if the monitor refresh rate could be changed on the fly, using some kind of method whereby it could read some code from the glasses being used to view the monitor, and it would lock onto a sync generated by the glasses or something to change the refresh and the flicker speed of the glasses to match. Then, only the first person viewing the monitor would see what he should see! Does this sound feasible?
Reason is the Path to God - Anon
I know that the science of polarization doesn't support it, but what if the "stealth screen" were blue instead of white? Then I suppose the USA Today article referring to hiding "your Windows desktop" would have to explain:
... blue screen ... stealth mode ... blue screen ... normal Windows malfunction.
Glasses off
Glasses on